Liner separation apparatus

ABSTRACT

Apparatus for separating an upper portion of a metallic liner from the inside wall of oil well production tubing to prepare said liner for removal therefrom. The apparatus includes a plurality of fingers which are pivotally mounted on a central body and are movable outwardly to an expanded position by an actuating sleeve. In the expanded position, the fingers are inserted between the liner and the tubing whereby the upper portion of the liner is separated from the tubing.

United States Patent Kinley et al. Aug. 7, 1973 1' LINER SEPARATION APPARATUS 3,073,389 1/1963 06 11161 166/55 x [75] Inventors: J C y, 5815 Royalton; 3,254,720 6/1966 Hultt et al 166/55 Charles W. Agee, both of Houston, Tex; Charles N- F C Primary Examiner-David 1-1. Brown Orleans, La. Attorney-Pravel, Wilson & Matthews [73] Assignee: said Kinley, by said Agee and Fowler [22] Filed: Dec. 27, 1971 [57] ABSTRACT [21] Appl. No.: 212,222

Apparatus for separating an upper portion of a metallic liner from the inside wall of oil well production tubing [52] U.S. Cl 166/55, 166/277, 166/297, to prepare said liner for removal therefrom The appa 166/315 ratus includes a plurality of fingers which are pivotally [5;] hit. Cl E21) 29/00 mounted on a central body and are movable outwardly [5 1 F16 0f S8Th l66/.55, 277, 315, to an expanded position y an actuating l In the 166/297, 178, 206, 211, 55.3, 72/ 370 expanded position, 1116 fingers are 111561166 between the liner and the tubing whereby the upper portion of the [56] References Cited liner is separated from the tubing.

UNITED STATES PATENTS 1,550,301 8/1925 Yungling 166/55 X 14 Claims, 4 Drawing Figures a K A 1 E! 66 M, 1; 226: 54a, LN 54 50x2 .53 47,--

PATENIEWB 1W 3.750.748

Zla

LINER SEPARATION APPARATUS BACKGROUND OF THE INVENTION l. Field of the Invention The field of this invention is apparatus for separating a portion of a liner from a tubular member such as oil well production tubing or casing so that the liner can be subsequently removed from the tubing.

2. Description of the Prior Art In oil wells it is sometimes necessary to repair weak spots or holes in production tubing. The holes may have been previously placed in the tubing for a specific purpose, such as a gas lift installation, and are now unwanted. Weak spots may be the result of corrosion or erosion caused by fluids flowing through the production tubing. In any event, it is extremely desirable that these holes or weak spots be covered without having to actually remove the weak or leaking tubing from the hole--a laborious and costly procedure which requires that the well be shut down and the tubing pulled.

Metallic linershave been found quite effective for covering up holes and otherwise patching downhole production tubing without having to pull the tubing. One type of metallic liner is a thin-walled steel tube coated on the outside with an oil-resistant elastomer to obtain a seal between the liner and the production tubing for sealing off the holes or weak spots.

Various means have been devised for setting such a metallic liner in production tubing; for instance, in US. Pat. No. 3,489,220, issued to M.M. Kinley, a method and apparatus is described for installing a liner having a reverse bend therein.

Although the metallic liners are extremely effective once installed properly, occasionally a newly installed liner does not effectively seal off the weak spot or hole in the tubing or is damaged in service and should be removed. Insofar as known, no one has devised an effective means for removing a liner from the production tubing. One of the difficulties in removing the, metallic liners is initially separating the top portion of the liner from. the production tubing. A reason for the difficulty is that the top end of the liner is beveled into the inside tubing wall so that most separating elements tend to slip off the top end of the liner when an attempt is made to insert the element betweentheliner and the tubing.

SUMMARY OF THE INVENTION An apparatus is provided which is adapted to be mounted on a wireline and lowered to a position substantially adjacent to the top end of the liner to be removed. The apparatus includes a pluralityof fingers mounted on a central body and movable or expandable outwardly for insertion between the top portion of the liner and the tubing inside wall thereby crimping the liner at one or more points and'separating the upper portion of the liner from the tubing so that the liner may be removed therefrom. An actuating means for moving the expandable fingers from a retracted position to an expanded position, in which the fingers are inserted between the liner and tubing, is released by upward movement of the apparatus after it has been positioned inthe production tubing substantially adjacent to the top of the liner.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of the apparatus of the present invention positioned in production tubing substantially above the top end of the liner which is to be separated from the tubing;

FIG. 2 is a sectional view of the apparatus with the expandable fingers inserted between the upper portion of the liner and the production tubing; and

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2 showing the configuration of the upper portion of the liner separated from the production tubing.

FIG. 3A is a sectional view taken along line 3A-3A of FIG. 2 showing the configuration at the top of the liner separated from the production tubing.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the drawing, the apparatus A is illustrated in position downhole in production tubing B for separating an upper portion C of a metallic liner D from the inner wall E of the production tubing. The apparatus A includes a central body designated generally at 10. The central body 10 includes a support 11 which has a male, threaded end 11a adapted for threaded connection to a tubing string or conventional wire line actuated jarring tool which is supported by a wire line thereabove (not shown). The central body of the apparatus further includes a mandrel 12 having a substantially longitudinal portion 12a that is mounted in a recess llb in the support by means of pins 13 and 14. The substantially longitudinal portion 12a of the mandrel has the downwardly facing shoulders 12b and 12c which engage the pins 13 and 14 mounted in apertures 11c and 11d in the recess 11b of the support 11. To mount the mandrel 12 in the recess 11b in the support 11, the longitudinal portion 12a of the mandrel is inserted into the recess 11b and the pins 13 and 14 are inserted through lateral holes such as 15 in actuator sleeve 31. g

A plurality of expandable fingers 20, 21, 22 and 23 (FIG. 3) are mounted on the mandrel l2for movement between a retracted positionillustrated in FIG; 1 and an expanded position illustrated in FIGS. 2 and 3 where the expandable fingers are inserted between the upper portion C of the liner and the production tubing toseparate the liner therefrom. Each of the expandable fingers 20-23 such asillustrated by fingers 20 and 22 in FIG. I are pivotally mounted in recesses such as 12d and 12a, respectively, by means of pivot pins 24 and 25. The expandable fingers 20, 21 and 22 shown in FIGS. 1 and 2 are tapered at their lower ends 20a, 21a and 22a for insertion between the top portion C of the liner and the inner wall E of the production tubing B. And, each expandable finger preferably has a convex outer surface 20b, 21b, 22b and 23b (FIG. 3) adapted to fit the concave contour of the inner wall E of the production tubing. It will be understood that finger 23 is constructed similar to the fingers 20, 21 and 22 and therefore it has not been shown in further detail.

An actuating means 30 is provided to pivot the expandable fingers from the retracted to the extended position. The actuating means includes an actuating sleeve 31 disposed slidably over a necked down portionlle of the support formed by a shoulder llf and over an enlarged portion 12f of the mandrel for movement relative thereto. Upward movement, in the direction of the arrow 32, of the actuating sleeve 31 from an initial position in FIG. 1 is limited by the shoulder 11f on the support. When the actuating sleeve 31 is moved downwardly to anactuating position illustrated in FIG. 2, an

inclined surface 31a on the sleeve engages a camming surface on each of the expandable fingers 20, 21, 22 and 23 such as the camming surfaces 200 and 220 for the fingers and 22, thereby pivoting the tapered ends outwardly against the inside wall of the production tubing (FIG. 2).

A compressed coil spring 40 is positioned about the longitudinal section 12a of the mandrel and engages bottom annular surface 11g on the support and upwardly facing shoulder 31b on the actuating sleeve to continually urge the actuating sleeve 31 downwardly into engagement with the camming surface on each of the expandable fingers 20-23.

To hold the sleeve 31 in the initial retracted position of FIG. 1 out of engagement with the fingers 2023 while the apparatus is lowered in the tubing B, a releasable means 50 is mounted on the support 11 for releasing the actuating sleeve by upward movement of the apparatus away from the liner in the production tubing. The releasable means includes a release lever 51 which has a hooked end 51a and is mounted on the support 11 for pivotal movement by the pin 52. The hooked end 51a of the release lever 51 is adapted to fit in a hole 310 in the actuating sleeve 31 with the release lever 51 in the position shown in FIG. 1. With the release lever in this position, a shear pin 53 extends through the release lever 51 and into a hole (not shown) in the support 11 to maintain the hooked end 51a in the hole 310 in order to prevent the coil spring 40 from moving the actuating sleeve 31 into engagement with the expandable fingers 20-23.

A latch dog 54 is pivotally mounted by means of the pin 55 extending through the latch dog 54 and into the support 11; and an extension spring 56 urges end 54b of the latch dog 54 against an upper edge 51b of the release lever 51.

OPERATION With the latch dog 54 in such pivoting position, the apparatus is lowered downhole in the production tubing B with the expandable fingers 20-23 being held inwardly by a band 58, which may be frangible wire, a paper tape, or any other means for temporarily holding the fingers 20-23 retracted so that their lower tips do not inadvertently catch in a collar or other part of the tubing B as the apparatus is lowered in the tubing B. As the apparatus is lowered into the production tubing B, the latch dog 54, which extends outwardly from the support 11, engages upwardly facing shoulders such as shoulder 59 of joint 60 in the production tubing; however, since the latch dog 54 is free to rotate in a counter-clockwise manner, the latch dog 54 will simply pivot upwardly to pass such shoulder and the spring 56 will keep it in contact with the inside surface of the joint or tubing B.

After the apparatus A has been positioned such that the tapered ends of the expandable fingers are positioned substantially adjacent on top end 65 of the liner, the apparatus is raised upwardly in the direction of arrow 32 such that the latch dog 54 engages downwardly facing shoulder 66 of the production tubing joint 60 thereby causing the latch dog to rotate clockwise. As the apparatus is pulled upwardly in the production tubing, the latch dog 54 continues to be rotated clockwise causing the corner of the latch dog 54 to be forcefully moved further into engagement with the release lever 51 until sufficient force is exerted on the release lever to shear the pin 53.

After the shearing of the pin 53, the latch dog 54 is rotated clockwise to force the release lever out of the hole 310 in the actuating sleeve to the position shown in broken lines in FIG. 1. With the release of the hooked end 51a from engagement with the actuating sleeve 31, the compressed coil spring 40 moves the actuating sleeve 31 downwardly such that the tapered surface 31a of the actuating sleeve engages the camming surfaces of the expandable fingers 20-23, such as camming surfaces 200 and 22c of the expandable fingers 20 and 22, thereby pivoting the tapered ends of the expandable fingers 20-23 against the inside wall of the production tubing B.

After the release lever 51 has been released from the hole 310 in the actuating sleeve, the force of the extension spring 56 rotates the latch dog 54 to the inactive position shown in the broken lines in FIG. 1 where the latch dog 54 will not interfere with the removal of the apparatus from the production tubing after the upper portion of the liner has been separated from the tubing, as will be more evident hereinafter.

With the expandable fingers 20-23 moved outwardly against the inside wall of the production tubing B, the apparatus is moved downwardly such that the tapered ends of the expandable fingers 20-23 are inserted between the upper portion C of the liner. and the inside wall E of the production tubing thus separating the upper liner portion C from the tubing. Of course, after the upper portion C of the liner D has been separated from the production tubing B, the apparatus is moved upwardly out of the production tubing B so that another tool or apparatus may be used to actually remove the liner D from the production tubing B.

In the preferred embodiment of this invention, four expandable fingers 20-23 are pivotally mounted on the mandrel l1 and are inserted between the liner D and the production tubing B. As the four expandable fingers 20-23 are moved further downwardly between the liner D and the production tubing B, the tapered ends of the expandable fingers 20-23 exert a wedging action which causes the top end 65 of the upper liner portion C to be moved further inwardly than the remainder of the upper portion C of the liner D. Also, each of the expandable fingers 20-23 has a convex inside surface such as surface 20d of the expandable finger 20 so that the expandable fingers deform four sections 70, 71, 72

and 73 of the upper portion C of the liner into a substantially concave configuration.

The force exerted inwardly by the downwardly moving adjacent expandable fingers also crimps the upper liner portion C at sections 74, 75, 76 and 77 thereby effectively reducing the diameter of the outer surface of the lining such that substantially none of the liner at the top end 65 is in engagement with the inside wall of the production tubing. Referring to FIG. 3, the .four expandable fingers provide four recesses or pockets, such as pocket 74a between the partially crimped sections or lobes 74 and 77 of the upper liner portion C; and, referring to FIG. 3A, the top end 65 of the liner D is crimped into four distinct lobes 74, 75, 76 and 77 such that another tool or apparatus can be conveniently inserted into a pocket such as 74a for removing completely the liner D from the tubing B;

It is within the scope of this invention to use less than four fingers 20-23 but it has been found that two expandable fingers such as and 22 are generally required and these are preferably positioned opposite to each other and thus, when inserted between the top liner portion C and the production tubing, would deform two sections 70 and 72 in the upper liner portion. In some cases, two adjacent expandable fingers such as 20 and 21 may be utilized to deform the upper liner portion at sections 70 and 71 and also form a crimped section 74 therebetween. Three expandable fingers can also be employed, however, just as with the use of two expandable fingers, the crimped sections such as 74 of the top portion C of the liner will remain in engagement with the inside wall of the tubing B. As previously described, insertion of the four expandable fingers 20-23 does completely separate the top portion C of the liner D from the tubing. Such complete separation is desirable because another tool can be inserted between the crimped sections or lobes such as 74 and the inside wall of the tubing B thus making the position of such a tool less critical.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention. For instance, it is within the scope of this invention to utilize the apparatus disclosed herein to remove liners made of other materials than thin-walled steel, the only limitation being that the linersmust be made of sufficiently yieldable material that they may be deformed without breaking up. Also, such liners as D are also used in casing or other tubular members. Thus, it is within the scope of this invention to remove liners from any such tubular members- We claim:

1. Apparatus for separating a liner from the insid wall of a tubular member, comprising:

a support body adapted to be placed in said tubular member; liner separating means for entry and longitudinal movement between the wall of the tubular member and the liner for deforming the liner inwardly relative to the tubular member; mounting means for mounting said liner separating means for movement between a retracted position out of engagement with the wall of the tubular member and an operating position between the wall of the tubularmember and the liner; and actuating means for moving said liner separating means from said retracted to saidoperating position.

2. The structure set forth in claim 1, including:

said liner separating means includes a separating element tapered at one end for insertion between said liner and the inside wall of said tubular memben 3. .Apparatus set forth in claim 1 wherein said support body includes:

a support adapted to be connected to a tool for moving said apparatus in said tubular member;

a mandrel releasably mounted on said support and extending therefrom; and

support mounting means mounting said liner separating means on said mandrel for movement between said retracted and operatingpositions.

4; The structure set forth in claim 1 wherein said liner separating means includes:

a plurality of liner separating elements; and

said mounting means mounting said elements for movement between retracted and operating positions for crimping and separating an upper portion of said liner from the wall of said tubular member upon insertion of said elements therebetween.

5. The structure set forth in claim 4 including:

band means extending about said liner separating elements to maintain said liner separating elements in said retracted position until said actuating means moves said liner separating elements to said operating position.

6. The structure set forth in claim 1, including:

said liner separating means including a separating element; and

pivotal means for pivotally mounting said separating element on said support body for movement between retracted and operating positions.

7. The structure set forth in claim 2, including:

an additional separating element and means mounting same for movement between retracted and operating positions on said support body substantially adjacent to said first-mentioned separating element whereby, upon insertion of said separating elements between said liner and said wall of said tubular member, substantially adjacent upper sections of said liner are separated from said tubular member and said liner is crimpedl between said upper sections.

8.'The structure set forth in claim2 including:

an additional separating element and means mounting same for movement between retracted and operating positions on said support body substantially opposite from said first-mentioned operating element whereby substantially opposite upper sections of said liner are separated from said tubular member upon insertion of said expandable ele' ments therebetween.

9. The structure set forth in claim 2 in which said separating element includes:

a substantially convex outside surface adapted to fit against the inner wall of the tubular member; and

a substantially convex inner surface adapted to engage the outside wall of said liner.

10. Thestructure set forth in claim 1 wherein said actuating means includes:

an actuating sleevedisposed slidably over said support body for movement relative thereto between an initial position out of engagement with said liner separating means and an actuated position in engagement with said liner separating means for moving saidliner separating means outwardly to said operating position.

11. The structure set forth in claim 10, including:

resilient means mounted over said support body in engagement with said actuating sleeve for urging said sleeve to the actuated position.

12. The device set forth in claim 10, including:

said liner separating means including a separating element pivotally mounted on said support body, said separating element having a camming surface thereon; and i said actuating sleeve including a surface for engaging said camming surface of said separating element to cause said separating element to pivot to said operating position.

13. The structure set forth in claim 10, including:

releasable means for releasably maintaining said actends through said release lever and said support tuating sleeve in said initial position; and b d d said releasable means releasing said actuating sleeve a latch dog pivotally mounted on Said Support body upon f a downwafdly facmg Shout" and extending therefrom whereby, upon movement f of sald tubular member,dm:mg movement 9 of said apparatus away from said liner, said latch said apparatus away from said liner whereby said dog engages said release lever with sufficient force actuating sleeve is movable to said actuating position to cause said shear pin to shear thereby allowing 14. The structure set forth in claim 13 wherein said Said release lever to pivot out of engagement with releasable means includes; said actuating sleeve and thus release said actuata release lever pivotally mounted on said support ing Sleeve for Slidable movement into engagement body, said release lever being held in engagement with said liner separating means.

with said actuating sleeve by a shear pin which ex- 

1. Apparatus for separating a liner from the inside wall of a tubular member, comprising: a support body adapted to be placed in said tubular member; liner separating means for entry and longitudinal movement between the wall of the tubular member and the liner for deforming the liner inwardly relative to the tubular member; mounting means for mounting said liner separating means for movement between a retracted position out of engagement with the wall of the tubular member and an operating position between the wall of the tubular member and the liner; and actuating means for moving said liner separating means from said retracted to said operating position.
 2. The structure set forth in claim 1, including: said liner separating means includes a separating element tapered at one end for insertion between said liner and the inside wall of said tubular member.
 3. Apparatus set forth in claim 1 wherein said support body includes: a support adapted to be connected to a tool for moving said apparatus in said tubular member; a mandrel releasably mounted on said support and extending therefrom; and support mounting means mounting said liner separating means on said mandrel for movement between said retracted and operating positions.
 4. The structure set forth in claim 1 wherein said liner separating means includes: a plurality of liner separating elements; and said mounting means mounting said elements for movement between retracted and operating positions for crimping and separating an upper portion of said liner from the wall of said tubular member upon insertion of said elements therebetween.
 5. The structure set forth in claim 4 including: band means extending about said liner separating elements to maintain said liner separating elements in said retracted position until said actuating means moves said liner separating elements to said operating position.
 6. The structure set forth in claim 1, including: said liner separating means including a separating element; and pivotal means for pivotally mounting said separating element on said support body for movement between retracted and operating positions.
 7. The structure set forth in claim 2, including: an additional separating element and means mounting same for movement between retracted and operating positions on said support body substantially adjacent to said first-mentioned separating element whereby, upon insertion of said separating elements between said liner and said wall of said tubular member, substantially adjacent upper sections of said liner are separated from said tubular member and said liner is crimped between said upper sections.
 8. The structure set forth in claim 2 including: an additional separating element and means mounting same for movement between retracted and operating positions on said support body substantially opposite from said first-mentioned operating element whereby substantially opposite upper sections of said liner are separated from said tubular member upon insertion of said expandable elements therebetween.
 9. The structure set forth in claim 2 in which said separating element includes: a substantially coNvex outside surface adapted to fit against the inner wall of the tubular member; and a substantially convex inner surface adapted to engage the outside wall of said liner.
 10. The structure set forth in claim 1 wherein said actuating means includes: an actuating sleeve disposed slidably over said support body for movement relative thereto between an initial position out of engagement with said liner separating means and an actuated position in engagement with said liner separating means for moving said liner separating means outwardly to said operating position.
 11. The structure set forth in claim 10, including: resilient means mounted over said support body in engagement with said actuating sleeve for urging said sleeve to the actuated position.
 12. The device set forth in claim 10, including: said liner separating means including a separating element pivotally mounted on said support body, said separating element having a camming surface thereon; and said actuating sleeve including a surface for engaging said camming surface of said separating element to cause said separating element to pivot to said operating position.
 13. The structure set forth in claim 10, including: releasable means for releasably maintaining said actuating sleeve in said initial position; and said releasable means releasing said actuating sleeve upon engagement with a downwardly facing shoulder of said tubular member during movement of said apparatus away from said liner whereby said actuating sleeve is movable to said actuating position.
 14. The structure set forth in claim 13 wherein said releasable means includes: a release lever pivotally mounted on said support body, said release lever being held in engagement with said actuating sleeve by a shear pin which extends through said release lever and said support body; and a latch dog pivotally mounted on said support body and extending therefrom whereby, upon movement of said apparatus away from said liner, said latch dog engages said release lever with sufficient force to cause said shear pin to shear thereby allowing said release lever to pivot out of engagement with said actuating sleeve and thus release said actuating sleeve for slidable movement into engagement with said liner separating means. 